A 51-year-old male was brought to the emergency room with fever and depressed consciousness. The family reported a 3-day history of asthenia, myalgia, stiffness of the neck, chills, and confusion. His medical history was relevant for chronic alcohol abuse and gout. On physical examination, the patient was febrile (39.2°C), hypertensive, and tachypneic. He was unconscious with no focal neurological deficits.
Urgent noncontrast computed tomography (CT) scan showed hydrocephalus with trans-ependymal edema with sparing of the fourth ventricle. The patient was intubated and an external ventricular drain was urgently inserted, which drained obviously purulent cerebrospinal fluid (CSF). The patient was started on a broad-spectrum antimicrobial therapy, which was later readjusted because CSF and blood cultures grew Streptococcus intermedius. The brain magnetic resonance imaging (Figure 1) scan revealed severe ventriculitis evidenced by intraventricular debris, intense enhancement of the ependymal lining of the ventricles associated with periventricular cerebritis, and multiple bilateral brain microabscesses.
Figure 1 Brain magnetic resonance imaging; axial fluid-attenuated inversion recovery (FLAIR) (A), diffusion-weighted imaging (B), apparent diffusion coefficient map (C), and T1 postgadolinium (D) images reveal intraventricular purulent material with a higher signal than CSF in FLAIR and diffusion restriction (asterisks in A-C). Intraparenchymal abscesses were also identified as rim-enhancing lesions with diffusion restriction within their centers (arrows in B-D). Ependymal enhancement related to ventriculitis was better demonstrated within both frontal horns (dashed arrows in D).
A chest and abdomen CT scan performed to search for a primary infection revealed a perforated diverticulitis complicated by multiple liver abscesses that were subsequently drained percutaneously.
During hospitalization, the patient eventually developed multiloculated hydrocephalus that required multiple drains and finally a ventriculopleural shunt after endoscopic fenestration of the ventricular septations. The patient improved remarkably and was awaiting rehabilitation when he suddenly died of a respiratory complication.
Discussion
Central nervous system infection is a very rare complication of diverticulitis.Reference Kamath, Mishra and Gunabushanam 1 - Reference Brewer, MacCarty and Wellman 4 To our knowledge, no case of purulent ventriculitis has been reported resulting from diverticulitis.
Although the Streptococcus anginosus group (S. anginosus, S. intermedius, and Streptococcus constellatus) is part of the normal gastrointestinal flora, it is rarely implicated in disseminated infections originating from a diseased colon.Reference Byrnes and Mazuski 5 When this is the case, multiple organs can be affected, most commonly the liver and the lungs.Reference Giuliano, Simone and Rubini 6 Alcoholism is a risk factor for such dissemination.Reference Mishra and Fournier 7 Even though the S. anginosus group is a common pathogen in brain abscesses,Reference Mofredj 8 , Reference Colnot, Alexandre and Arnaudo 9 it usually spreads contiguously from sinusitis or mastoiditis, which often develops into a single brain abscess. Only two cases of S. anginosus brain abscesses resulting from diverticulitis, though not ventriculitis, have been reported in the literature.Reference Kamath, Mishra and Gunabushanam 1 , Reference Dixon a, Holmes and Waters 3
S. intermedius has an apparent tropism for the brain and liver.Reference Giuliano, Simone and Rubini 6 This characteristic can be explained by the difference of virulence factors produced by the S. anginous group species.Reference Mishra and Fournier 7 S. intermedius produces the enzymes α-N-acetylneuramidase (sialidase), a growth factor, and hyaluronidase, which destroy host tissues. S. constellatus produces only hyaluronidase. S. anginosus produces neither. Also critical for the pathogenicity of S. intermedius is the involvement of hyaluronidase in the formation of biofilm that protects it from host defenses and antibiotics.Reference Mishra and Fournier 7
Conclusion
Purulent ventriculitis can be a complication of diverticulitis. S. intermedius, found in normal intestinal flora, has an affinity for invading the brain. Isolation of S. intermedius from CSF should raise suspicion for an abdominal source of infection. Consequently, this widens the spectrum of possible sources a neurosurgeon has to consider when a patient presents with ventriculitis.
Disclosures
None of the authors has anything to disclose.
